Background: Renal anemia, one of the causes of anemia, has inflicted a certain degree of loss on global health. However, there are no comprehensive analyses on the burden of renal anemia yet. This study aims to comprehensively evaluate the age-standardized prevalence and Years Lived with Disability (YLDs) burden and trends of renal anemia across different sexes, ages, countries, and regions from 1990 to 2021. Methods: We analyzed the prevalence and YLDs of renal anemia from 1990 to 2021 across different sexes, ages, countries, and regions. We also examined the relationship between the burden of renal anemia in various regions and the Human Development Index (HDI). Further analyses included the changes in the rank of renal anemia among causes of anemia from 1990 to 2021. Finally, we conducted health inequality analysis, frontier analysis, and APC (age-period-cohort) model analysis on the burden of renal anemia. Results: In 2021, the global prevalence of renal anemia across all age groups was 0.82% (95% uncertainty interval [UI] 0.73 - 0.91), equivalent to 63.92 million (59.61 - 71.81) prevalent cases, resulting in 1.70 million (1.13 - 2.43) years lived with disability (YLDs), showing an increase compared to 1990. In recent years, renal anemia has risen in rank among causes of anemia. The burden of renal anemia varies significantly across different age groups and regions, with particularly severe burdens observed among populations over sixty years of age in Central Europe, Eastern Europe, Central Asia, South Asia, Southeast Asia, southern Latin America, and North American countries. A series of analyses based on the HDI revealed the following: descriptive analysis indicated a positive correlation between the prevalence of renal anemia and HDI; cross-national inequality analysis showed an increasing disparity in prevalence and YLDs between high HDI and low HDI countries, with higher burdens in high HDI countries; although with low prevalence, frontier analysis revealed considerable opportunities to reduce the age-standardized YLDs in the Low and medium of HDI spectrum; APC analysis suggested significant differences in the prevalence of renal anemia in high HDI regions (not very high HDI regions) compared to middle and low HDI regions across age, period, and cohort analyses. Conclusions: Although the global burden of anemia is decreasing, renal anemia remains a significant health issue, especially among older populations in mid and high-development countries. Targeted programs should be implemented, starting with enhancing diagnosis and treatment in specific regions and populations. The development of new medications should also be considered.